Reversible cycle ice maker

ABSTRACT

An ice maker comprising a compressor fluidly connected to two refrigerant coils, each coil in heat transfer relation with a corresponding water tube. Reversing valves alternately divert the refrigerant to the first and second coil to alternately produce ice in one of the tubes and to harvest ice in the other of the tubes.

United States Patent [191 Cochran 1 Sept. 18, 1973 REVERSIBLE CYCLE ICE MAKER [76] Inventor: Charles C. Cochran, 2467 Haymaker Dr., Monroeville, Pa. 15146 [22] Filed: July 28, 1971 [21] Appl. No.: 166,836

[52] US. Cl. 62/73, 62/348 [51] Int. Cl. F25c 1/12 [58] Field of Search 62/73, 352, 348,

[56] References Cited UNITED STATES PATENTS 2,787,890 4/1957 Muffly 62/352 3,464,226 9/l969 Kramer 62/278 X Primary Examiner-William E. Wayner Attorney-Bruce L. Samlan [57] ABSTRACT An ice maker comprising a compressor fluidly connected to two refrigerant coils, each coil in heat transfer relation with a corresponding water tube. Reversing valves alternately divert the refrigerant to the first and second coil to alternately produce ice in one of the tubes and to harvest ice in the other of the tubes.

11 Claims, 2 Drawing Figures Patented Sept. 18, 1973 3,759,048

\0000000 oooobou 2 62 0000a fluooP Poo on oo TO POWER SUPPLY A COMP I8 92 P 62 FIG. 2 -61 75 @55 L INVENTOR Charles C. Cochran ATTORNEY REVERSIBLE CYCLE ICE MAKER BACKGROUND OF THE INVENTION The following disclosure relates to ice makers and more specifically to the types that are used in public eating and drinking places where the demand for a large commercial quantity of ice cubes are needed.

Ice machines of this type are automatic in operation as they continually freeze the ice, harvest the ice and store it in a suitably insulated container until it is required for use. Furthermore, means are provided for stopping the continuous freezing process when the storage container is filled and resuming the freezing cycle automatically when the stored quantity is reduced.

It is to be understood that when the term ice cube is used the word cube is not to be taken literally. As is well known in the art, any suitably shaped ice pieces can be made.

The basic ice forming cycle used in present ice makers is the common vapor-compression cycle which includes a compressor to pump refrigerant gas and a restrictor which creates a high and low pressure zone. The condenser (commonly water cooled) being in the high pressure zone is used to condense the gas into a 7 liquid by removing and discharging heat to the environment. The evaporator being in the low pressure zone causes liquid refrigerant to vaporize, thus absorbing heat from the water to create ice. Further included are means to harvest the formed ice and regulating means to control the ice forming cycle and the ice harvesting cycle. The standard type of ice makers are shown in U.S. Pat. Nos. 2,775,098 and 2,784,563.

There are a multitude of problems encountered in the aforedescribed ice makers. Present ice machines only produce ice a portion of the time since there is a considerable harvesting cycle. Furthermore, most harvesting cycles presently utilize a hot gas bypass system to dislodge the ice cubes when formed and this produces a severe strain on the compressor and shortens the useful life thereof. Another serious problem in present ice makers is that the water recirculated in the evaporator to make ice becomes stagnant, causing substantial concentration of minerals and biological growths to deposit in the water reservoir and on the ice forming pipes. This results in appreciable loss in refrigeration capacity of the device and in certain extreme circumstances has created a health hazard. This is more fully disclosed in U.S. Pat. No. 2,775,100.

Furthermore, since municipal water is used, deposits are formed on the condenser coils so that a commercial scale removal cleaner can be utilized to remove the deposits. This procedure is very time consuming and expensive.

Another problem in current ice makers is that a large quantity of water is used to cool the condenser portion which flows down the drain. correspondingly, large water bills are a necessary overhead to the commercial user of the standard ice making machines, this problem becoming more severe as commercial usable water decreases.

It would be desirable then to design an ice making machine which would have increased capacity, which would increase the life of the compressor by eliminating the hot gas bypass, which would minimize the deposits and biological growths in the water recirculation system, and which would substantially decrease the amount of water being used.

SUMMARY OF THE INVENTION The following relates to an ice making machine and more specifically to a machine which is of the water cooled type.

The invention includes in combination, a compressor connected to a first refrigerant coil, the first coil in heat transfer relation with a first water tube, a second refrigerant coil in heat transfer relation with a second water tube, the second coil being connected to the compressor and the first coil, and at least one reversing or diverting valve to alternately direct the coolant from the compressor to the first and second coils. When the refrigerant is diverted to the first coil, the first coil condenses the refrigerant and the second coil acts as an evaporator to produce ice in the second water tube. The refrigerant is then diverted to the second coil to harvest the ice in the second tube and also to condense the refrigerant in the second coil. The condensed refrigerant then flows to the first coil where the refrigerant is vaporized and produces ice in the first tube.

Therefore, this ice maker can continually form ice in one of the tubes and can thereby substantially increase the amount of ice produced per unit time when compared to present ice makers. The hot gas bypass harvest cycle is eliminated since the gas is not passed directly through the evaporator, and back to the compressor since it first passed through the condenser and restrictor. This substantially increases the life of the compressor. The water used to cool the condenser is recirculated and the quantity is substantially reduced. The water is flushed to minimize the mineral and biological deposits.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic representation of an ice making apparatus formed in accordance with the principles of the present invention;

FIG. 2 is a simplified electrical schematic of a portion of the ice maker.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings in detail and particularly FIG. 1, there is shown an ice machine 10 comprised of an insulated cabinet 1 l. The cabinet 11 is comprised of four separate compartments: the upper compartment 13, the two central side-by-side compartments l4 and 15, and the bottom compartment 16, which is the ice storage bin.

Disposed within the upper compartment 13 is a compressor l8 and two refrigerant diverting or reversing valves 20 and 21, which may be of the type shown in U.S. Pat. No. 2,785,540. The compressor 18 is fluidly connected to valve 20 by refrigerant conduit 23 and is fluidly connected to valve 21 by refrigerant conduit 24. The diverting valves 20 and 21 are fluidly connected to each other by refrigerant conduits 26 and 27. Also disposed within compartment 13 is a water supply conduit 29 which may be from any suitable source such as a municipal water supply. A water regulating valve 30 is disposed in the water conduit 29, the valve 30 sensing the pressure of the coolant in conduit 24 via line 31. Disposed downstream of regulating valve 30 in conduit 29 is a water diverting valve 33. Upstream of the regulating valve 30 at junction 34 is a water supply line 36.

In central compartment 15, there is disposed a first refrigerant coil 38, which is fluidly connected to diverting valve 21. The refrigerant conduit 40 secures the refrigerant coil 38 to the diverting valve 21. Secured to the coil 38, by any suitable means, are a plurality of vertical water tubes 42 in heat transfer relation with coil 38. Secured to the refrigerant coil 38 is thermostat 45 or any other suitable thermal device.

Refrigerant conduit 47 and bypass conduit 48 are fluidly connected to the coil 38. Restrictor means 50 is disposed in conduit 47 and check valve 51 is disposed in bypass conduit 48. I

A water manifold 53 is disposed above water tubes 42. Conduit 54 connects water diverting valve 33, the junction 55, and conduit 56 to the manifold 53.

Disposed beneath the water tubes 42 is sump 57. The sump 57 is fluidly connected to the water supply conduit 29 by line 36. The amount of water entering the sump 57 is regulated by a floating device 58 which regulates valve 59. Overflow drain 60 controls the height of the water in sump 57. A water pump 62 recirculates the water in sump 57 to the water manifold 53 through water conduit 61. An ice deflecting grid 63 is disposed between the water tubes 42 and the sump 57 to deflect the ice from the water tubes to the ice storage bin 16.

In the central compartment 14 of the ice machine 10, there is similarly disposed a second refrigerant coil 68 fluidly connected to diverting valve 20 by refrigerant conduit 70. A plurality of vertically extending water tubes 72 are firmly secured to the coil 68, by any suitable means and are in heat transfer relation therewith. Thermostat 75 or any other suitable thermal device is secured to the coil 68. Refrigerant conduit 47 (compartment 15) is fluidly connected to coil 68 via conduit 79. Bypass conduit 78 is disposed therearound. Restrictor means 80 is disposed in conduit 79 and check valve 81 is disposed in bypass conduit 78. Water manifold 83 is disposed over the water conduits 72 in a manner well known in the art. Water conduit 84 fluidly connects the diverting valve 33 through junction 85 and conduit 86 to the manifold 83.

A sump 87 is disposed beneath the water tubes 72. A floating device 88 regulates the water valve 89 to control the amount of water entering the sump 87 through water supply line 36. Water overflow drain 90 controls the level of water in the sump 87. Water pump 92 recirculates the water from sump 87, the conduit 91 to the manifold 83, flowing through junction 85 and conduit 86. An ice deflecting grid 93, disposed between the water pipes 72 and the sump 87, deflects the ice from the water tubes to the ice storage bin 16.

FIG. 2 represents a simplified electrical schematic showing thermostats 75 and 45 in combination with the reversing valves 33, 20, and 21, water pumps 92 and 62, and a cycle reversing device, such as a reversing relay 95. Safety devices, such as overloads and pressure switches, have been eliminated for purposes of simplicity. The reversing relay 95 may be activated by any suitable device (not shown) such as a timer, thermostat, pressure switch, or mechanical switches, to alternately reverse the ice making and harvesting in tubes 42 and 72.

In operation, the compressor 18 pumps any suitable refrigerant, such as Freon, in the direction indicated by the solid arrow into conduit 24. The Freon flows through diverting valve 21 to conduit and into the refrigerant coil 38.

To maintain a cool condensed refrigerant, water is pumped from sump 57 by pump 62 through conduit 61, junction 55 and conduit 56 into manifold 53. The water level in sump 57 is maintained by means of float 58 which controls the flow of water from conduit 36 which enters the sump 57 by way of valve 59. Water is entering the water supply conduit 29 and flows through the regulating valve 30, diverting valve 33, conduit 54, junction 55, conduit 56, into the water manifold 53. This cool water maintains proper condensing temperature of the water in sump 57. The water, through any suitable openings in the bottom of the manifold 53, flows downwardly through the vertical water tubes 42. The refrigerant in coil 38 is thereby condensed into a liquid, the combination of the tubes 42 and coil 38, functioning as a condenser. in this manner fresh water during this operation is continually flushing the sump 57. The water passing through the vertical tubes 42 flows into the sump 57. Excess water leaves the sump 57 by an overflow drain 60. The coolant exits from coil 38 and flows into bypass conduit 48 and through check valve 51 in the direction indicated by the solid arrow.

The coolant then flows into conduit 79 and through the refrigerant restrictor means 80, which may be of the expansion valve type or the capillary type. The refrigerant goes from conduit 79 to coil 68 in compartment 14, where it begins to vaporize.

The water level in sump 87 is maintained by float 88 and water valve 89 which also aids in flushing the sump. Pump 92 pumps water to the manifold 83, via conduit 91, junction 85, conduit 86, and gravity returns it back to sump 87. The water flows downwardly through suitable apertures in manifold 83 into the vertical tubes 72 where heat is transferred to refrigerant coil 68 causing the refrigerant to change state from a liquid to a vapor. Therefore, ice is formed in the tubes 72.

In the manner shown, the ice is formed at the contact of the coil 68 with the tubes 72 as indicated by the numerals 99. The combination of the vertical tubes 72 and the coils 68 function as an evaporator in this ice making cycle.

The coolant leaves coil 68 and flows through conduit 70, diverting valve 20 and conduit 23 to the compressor 18. This cycle of making ice in compartment 14 continues until the ice is ready to harvest.

Any suitable means well known in the art may be used to determine when the ice is ready for harvest, such as a thermostat, timer or pressure switch. As shown in FIG. 2, cycle reversing relay 95 electrically diverts valves 20, 21 and 33 to reverse the flow of the refrigerant and the water respectively. During the initial harvesting cycle it is desirable that water flow be cut off through the tube 72. Thermostat secured to coil 68, delays the pump 92 from starting until the ice is harvested. Furthermore, water will not enter through conduit 84, since the regulating valve 30 isclosed and since the pressure of the coolant in conduit 24 is too low.

The coolant which was relatively hot as it leaves the compressor then flows through conduit 24, through diverting device 21 as indicated by the dotted arrow, conduit 26, diverting valve 20, conduit 70, and into the coil 68. The ice in tubes 72 condenses the coolant in the coil 68, and because of the lower temperature of the ice, it is a much more effective condenser than if just plain municipal cooling water was used. Additionally, however, the coolant melts the ice in the tubes 72 to allow the ice cubes to move vertically downward onto the ice deflecting grid 93 and into the ice storage bin 16. At this point, the thermostat 75 closes thus activating pump 92 to distribute water into the manifold 83. When the ice is harvested, pump 92 starts and the water from sump 87 condenses the coolant. When this water becomes too hot, the coolant in conduit 24 increases in pressure causing more cooling water to enter manifold 83 via valves 33 and 30.

The coolant exits from coil 68 and flows through bypass conduit 78, through check valve 81, in a direction indicated by the dashed arrow. The condensed coolant then flows through a restrictor 50, similar to restrictor 80 and goes into coil 38. The coil 38 in combination with the vertical tubes 42 operates as an evaporator to produce ice in compartment in a similar manner to that described for producing ice in compartment 14.

The coolant leaves coil 38 and goes through conduit 40, diverting valve 21, conduit 27, diverting valve 20, conduit 23, and back into the compressor 18. This cycle continues until ice is formed in compartment 15. Then the cycle reversing relay 95 (FIG. 2) in response to a signal from a thermostat timer, or pressure switch (not shown) switches the diverting valves 20, 21 and 33 to reverse the flow of the refrigerant and water respectively. During this time, thermostat 45 opens to discontinue operation of pump 62 and the water regulating valve is closed until the ice is harvested in compartment 15.

it can be seen therefore that there are substantial advantages of using this type of reversing cycle ice maker. Ice is continuously being produced in either of the two compartments 14 or 15. Therefore the capacity of the ice maker is substantially increased. In conventional ice makers, as previously mentioned, to achieve the similar type of capacity required two complete units which of course required two compressors, which forms the most expensive single part of the ice machine. In applicants machine only a single compressor, of the same size is required. Another advantage of the applicants ice machine is that the hot gas bypass harvest cycle is eliminated thereby further increasing the life of the compressor. Furthermore, the costly coil which is used solely as a condenser is eliminated. Another advantage is that the sumps 57 and 87 are continually being purged of stagnant water which will reduce the amount of minerals and biological accumulation that occur therein.

This results in less accumulations of deposits in the water tubes 42 and 72. Additionally, since water tubes 42 and 72 have corresponding pumps 62 and 92, re spectively, easier servicing is available to remove the scale deposited therein, and the costly procedure of adding an external pump to remove the scale from the standard condenser is eliminated. Finally, there is a substantial savings in water because the water being used to condense the coolant is being recycled. Furthermore, the applicant uses the ice itself to help condense the gas.

Although only one embodiment has been shown, it is intended that all the matter contained in the foregoing description and as shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a structure for making ice,

a compressor to compress the refrigerant,

a first refrigerant coil,

conduit means fluidly connecting said first coil to said compressor,

a first water tube in heat transfer relation with said first coil,

a second refrigerant coil,

conduit means fluidly connecting said first and second coils,

a second water tube in heat transfer relation with said second coil,

refrigerant restrictor means in the conduit between the first and second coil, conduit means fluidly connecting said second refrigerant coil to said compressor,

means to supply said water to said first and second tubes,

means to divert the compressed refrigerant to either said first or second coils, to alternately produce ice in one of said tubes, and to harvest the ice in the other of said said tubes,

said combination of said first coil and said first tube being a condenser during one cycle and an evaporator in the other cycle, said combination of said second coil and said second tube being an evaporator during said one cycle and a condenser during said other cycle, and

said combination of said first coil and said first tube being the sole condenser of the refrigerant supplied to the corresponding evaporator during said one cycle.

2. The structure recited in claim 1, wherein the water flows through the first tube when the diverting means directs the compressed refrigerant to the first coil,

the water condensing said refrigerant in the first coil,

the condensed refrigerant passing through the restriction means and expanding upon entering said second coil,

the refrigerant in said second coil vaporizing to thereby make ice in the second tube.

3. The structure recited in claim 2 and further including means actuating said diverting means when said ice is ready to harvest in the second tube,

said diverting means directing the refrigerant from the compressor to the second coil to harvest the ice from the second tube, and

said ice condensing the refrigerant.

4. The structure recited in claim 3 wherein the refrigerant flows through the restrictor means before entering the first coil,

the refrigerant vaporizing upon entering the first coil to cool the water in the first tube to make ice therein, and

wherein the coolant flows back to the compressor after leaving the first coil.

5. The structure recited in claim 1 wherein the water supply means isolates the water supplied to the first and second tubes and comprises means to provide fresh water to the water tubes and means to recirculate water to the respective tubes.

6. The structure recited in claim 5 wherein means are provided to cut off the supply of water to the tube in which ice is being harvested.

7. The structure recited in claim 5 wherein means are provided to add fresh water to the water recirculating means to periodically purge the water recirculating system with the fresh water and furthermore to maintain water temperature.

8. The structure recited in claim 1 wherein the first coil condenses the refrigerant while the second coil vaporizes the refrigerant, and alternately, the second coil condenses the refrigerant while the first coil vaporizes the refrigerant.

9. A method of making ice comprising the steps of:

l. compressing the refrigerant,

2. condensing the refrigerant in a first coil structure in heat transfer relation with a first water tube,

3. vaporizing the refrigerant in a second coil structure and forming ice in a second water tube,

4. reversing the flow of the refrigerant in the second coil structure,

5. harvesting the ice in the second water tube and condensing the refrigerant in the second coil structure, and

6. providing cooling for the second coil structure after ice is harvested from the second water tube.

10. The method recited in claim 9 and further including the steps after step of:

conduit means fluidly connecting said first coil to" said compressor,

a first water tube in heat transfer relation with said first coil,

a second refrigerant coil,

conduit means fluidly connecting said first and second coils,

a second water tube in heat transfer relation with said second coil,

refrigerant restrictor means in the conduit between the first and second coil,

conduit means fluidly connecting said second refrigerant coil to said compressor,

means to supply said water to said first and second tubes,

means to divert the compressed refrigerant to either said first or second coils, to alternately produce ice in one'of said tubes, and to harvest the ice in the other of said tubes,

said means to supply water to said first tube comprising a water pump,

said pump supplying water to said first tube to produce ice in said first tube, and

time delay means associated with said pump to prevent said pump from supplying water to said first tube until after said ice is harvested from said first tube. 

1. In a structure for making ice, a compressor to compress the refrigerant, a first refrigerant coil, conduit means fluidly connecting said first coil to said compressor, a first water tube in heat transfer relation with said first coil, a second refrigerant coil, conduit means fluidly connecting said first and second coils, a second water tube in heat transfer relation with said second coil, refrigerant restrictor means in the conduit between the first and second coil, conduit means fluidly connecting said second refrigerant coil to said compressor, means to supply said water to said first and second tubes, means to divert the compressed refrigerant to either said first or second coils, to alternately produce ice in one of said tubes, and to harvest the ice in the other of said said tubes, said combination of said first coil and said first tube being a condenser during one cycle and an evaporator in the other cycle, said combination of said second coil and said second tube being an evaporator during said one cycle and a condenser during said other cycle, and said combination of said first coil and said first tube being the sole condenser of the refrigerant supplied to the corresponding evaporator during said one cycle.
 2. The structure recited in claim 1, wherein the water flows through the first tube when the diverting means directs the compressed refrigerant to the first coil, the water condensing said refrigerant in the first coil, the condensed refrigerant passing through the restriction means and expanding upon entering said second coil, the refrigerant in said second coil vaporizing to thereby make ice in the second tube.
 2. condensing the refrigerant in a first coil structure in heat transfer relation with a first water tube,
 2. vaporizing the refrigerant in the first coil structure to make ice in the first water tube.
 3. vaporizing the refrigerant in a second coil structure and forming ice in a second water tube,
 3. The structure recited in claim 2 and further including means actuating said diverting means when said ice is ready to harvest in the second tube, said diverting means directing the refrigerant from the compressor to the second coil to harvest the ice from the second tube, and said ice condensing the refrigerant.
 4. The structure recited in claim 3 wherein the refrigerant flows through the restrictor means before entering the first coil, the refrigerant vaporizing upon entering the first coil to cool the water in the first tube to make ice therein, and wherein the coolant flows back to the compressor after leaving the first coil.
 4. reversing the flow of the refrigerant in the second coil structure,
 5. harvesting the ice in the second water tube and condensing the refrigerant in the second coil structure, and
 5. The structure recited in claim 1 wherein the water supply Means isolates the water supplied to the first and second tubes and comprises means to provide fresh water to the water tubes and means to recirculate water to the respective tubes.
 6. The structure recited in claim 5 wherein means are provided to cut off the supply of water to the tube in which ice is being harvested.
 6. providing cooling for the second coil structure after ice is harvested from the second water tube.
 7. The structure recited in claim 5 wherein means are provided to add fresh water to the water recirculating means to periodically purge the water recirculating system with the fresh water and furthermore to maintain water temperature.
 8. The structure recited in claim 1 wherein the first coil condenses the refrigerant while the second coil vaporizes the refrigerant, and alternately, the second coil condenses the refrigerant while the first coil vaporizes the refrigerant.
 9. A method of making ice comprising the steps of:
 10. The method recited in claim 9 and further including the steps after step 5 of:
 11. In a structure for making ice, a compressor to compress the refrigerant, a first refrigerant coil, conduit means fluidly connecting said first coil to said compressor, a first water tube in heat transfer relation with said first coil, a second refrigerant coil, conduit means fluidly connecting said first and second coils, a second water tube in heat transfer relation with said second coil, refrigerant restrictor means in the conduit between the first and second coil, conduit means fluidly connecting said second refrigerant coil to said compressor, means to supply said water to said first and second tubes, means to divert the compressed refrigerant to either said first or second coils, to alternately produce ice in one of said tubes, and to harvest the ice in the other of said tubes, said means to supply water to said first tube comprising a water pump, said pump supplying water to said first tube to produce ice in said first tube, and time delay means associated with said pump to prevent said pump from supplying water to said first tube until after said ice is harvested from said first tube. 